I like the idea of Service Packs. A roll up of further tested CUs bundled together. My guess is they are moving resources away from creating SPs and into new version work. Think of how many man hours it would take to put together and test a SP for SQL2008, SQL2008R2, SQL2012 all at the same time. Personally today, when I build a new server for SQL 2008R2 I patch it to SP2 and CU7 and that is my starting point which is June of 2013.